WASHINGTON — A trip to Taiwan that Rep. Peter Roskam took with his wife in 2011 has been referred to the House ethics committee at the urging of an outside panel that found he may have violated House rules and federal law in accepting the $25,000-plus excursion, according to ethics officials and the congressman's office.

Roskam, 51, a Republican from Wheaton who entered Congress in 2007, is his party’s chief deputy whip in the House, a leadership role that includes vote counting and messaging.

The crux of the ethics matter is who paid for the eight-day, $25,653 trip taken by Roskam and his wife, Elizabeth, at a time when their daughter was teaching in Taiwan.

He and his lawyers maintain that the Chinese Culture University in Taipei sponsored the trip, a mix of meetings with government officials and sightseeing.

But the independent Office of Congressional Ethics, whose investigation resulted in a referral to the House ethics committee, contended that the Roskams' trip may have constituted what is called an "impermissible gift" because of the involvement of the Taipei Economic and Cultural Representative Office (TECRO) in the United States. That office is an arm of Taiwan's government.

In a statement Friday, Roskam spokeswoman Stephanie Kittredge said the lawmaker "fully complied with all laws, rules and procedures" governing congressional trips sponsored by private sources.

She released more than 60 pages of documents about the trip, which took place Oct. 15-22, 2011. Included were the findings of the Office of Congressional Ethics, which voted 6-0 on May 31 to forward its conclusions to the more powerful ethics committee.

The House ethics committee, in a short statement Friday, declined to say what the Roskam "matter" involved — but the disclosures from the congressman's office bring the matter into sharp focus. The independent ethics office found that the trip appeared to be "organized and conducted by the government of Taiwan, with little or no involvement by the University."

The rules governing congressional travel are long and arcane. Foreign government can't pay for lawmaker trips except when they are cultural exchanges authorized under the Mutual Educational and Cultural Exchange Act (MECEA). Under such trips, however, no travel money can flow to a family member of a lawmaker.

Roskam was invited to Taiwan in May 2011 for a MECEA trip sponsored by the Taiwanese government, the ethics office said. He ultimately decided to travel to Taiwan with his wife and it was determined that the trip instead would be privately sponsored, the office said.

The ethics office said the Taipei university was a "non-cooperating witness" in its probe and that TECRO declined to provide documents or make officials available for interviews.

On Friday, the Office of Congressional Ethics had no comment on the case. The non-partisan entity lacks the muscle of the House ethics committee, which may subpoena documents and witnesses and compel testimony under oath as it examines lawmaker conduct. The committee – unlike the office – also has the power to sanction lawmakers who violate the law or House rules. The committee had no comment Friday beyond its statement.

In a statement Friday, the ethics committee's Republican chairman and top Democratic member said the outside panel transmitted the matter to them June 13. The two lawmakers said their statement did not indicate a violation had occurred nor did it reflect a judgment by the committee. The two also said the committee will "announce its course of action" in the case on or before Sept. 11.

The board of the outside ethics panel found "there is substantial reason to believe that Representative Roskam accepted payment of travel expenses for an officially connected trip to Taiwan from an impermissible source, resulting in an impermissible gift, in violation of federal law and House rules," the documents show.

Roskam and his attorneys, from the Patton Boggs firm in Washington, emphasized in writing to ethics officials — at both the outside panel and the committee — that the same House ethics committee had pre-approved the Roskams’ Taiwan trip. They said Chinese Culture University sponsored the trip in a manner consistent with rules governing privately sponsored travel.

A story in the Daily Herald in 2011 said the lawmaker's daughter, Gracey Roskam, spent a year in Taiwan teaching English to second graders and Skyped weekly with her family. By 2012, she was working at the Republican National Convention as an executive assistant to the GOP's platform committee, party officials said.

Kittredge, Roskam's spokeswoman, said in her statement that the ethics office was "wrong to take issue with the involvement of the Government of Taiwan in planning and conducting the trip, a matter that is routine, allowed under the law, and was known to the House Ethics Committee as they thoroughly vetted and approved the trip."

She said Roskam will continue to fully cooperate in the matter and already has made himself and his staff available for interviews. "He fully expects the clear and indisputable facts of the case to speak for themselves, that both he and his staff have acted in accordance with all laws, rules, and regulations," she said.

Roskam travels abroad regularly. A Tribune review of congressional travel during the years 2009 and 2010 found he had made four trips abroad during that time to five countries: El Salvador, Guatemala, Panama, Israel and South Korea.

The west suburban congressman first won a House seat in 2006 in a hard-fought contest against Democrat Tammy Duckworth, who ran again last year in a different district and won. Roskam serves on the tax-writing Ways and Means Committee.